AVI BioPharma Scientists Publish Results of Antisense Drug in Treating Cancer and Viral Infections.

Business Editors & Health/Medical Writers

PORTLAND, Ore.--(BW HealthWire)--May 14, 2002

NEUGENE Antisense Drugs Making Solid Progress in Treating Prostate

Cancer and Calicivirus Infections

AVI BioPharma, Inc. (Nasdaq:AVII) (Nasdaq:AVIIW) (Nasdaq:AVIIZ) today announced the publication of two studies in Current Opinion in Molecular Therapeutics (2002) 4(2).

These preclinical studies demonstrated potential for use of AVI's third-generation antisense drug platform, NEUGENE(R), in treating prostate cancer and viral infections caused by the Caliciviridae, a family of RNA viruses.

"AVI continues to build strong scientific support for its antisense technology," said Patrick L. Iversen, Ph.D., AVI's senior vice president of research and development. "These studies confirm our belief that NEUGENE compounds are capable of addressing a broad range of health problems for which there are no known cures."

Antisense as a Treatment for Prostate Cancer

Prostate cancer is the most frequently diagnosed malignancy and is the most common cause of mortality among men. In "Prostate cancer: Status of current treatments and emerging antisense-based therapies," Gayathri Devi, Ph.D., senior scientist at AVI, compared current prostate cancer treatment strategies with preclinical and clinical prostate cancer antisense studies conducted in the past year. Dr. Devi reviewed stages and treatment options for prostate cancer, which were linked to the antisense approach. Her research showed that AVI's antisense technology is an attractive alternative to traditional cancer therapies.

Antisense as a Treatment for Viral Infections

Approximately 175 known calicivirus isolates have been recovered from animals ranging from shellfish to cattle by the Laboratory for Calicivirus Studies at Oregon State University. Many of these isolates and other caliciviruses are capable of infecting humans, and some scientists believe they cause non-A through E hepatitis. Calicivirus infections can result in one or more of the following: diarrhea, hepatitis, encephalitis, pneumonia, hemorrhage and other conditions in animals and humans. In "Antisense treatment of Caliciviridae: An emerging disease agent of animals and humans," AVI scientists David A. Stein, Andrew D. Kroeker and Patrick L. Iversen, Ph.D., in conjunction with Alvin Smith, DVM, Ph.D., from Oregon State University and David O. Matson, MD, Ph.D., from the Center for Pediatric Research in Norfolk, Va., showed that AVI's antisense technology platform is effective against viral infection. This NEUGENE platform may effectively solve the unique problem of identifying new therapeutic agents for emerging viral infections.

About AVI BioPharma

AVI BioPharma develops therapeutic products for the treatment of life-threatening diseases using two technology platforms: NEUGENE antisense drugs and cancer immunotherapy. Its lead cancer agent, AVICINE(R), a therapeutic cancer vaccine, has completed three Phase II trials in colorectal and pancreatic cancer and is initiating a Phase III pivotal trial in pancreatic cancer, with a supporting study in colorectal cancer. The first application of its NEUGENE compounds, Resten-NG(TM), is designed to treat cancer, cardiovascular restenosis and other cell proliferation disorders by inhibiting the production of a cellular transcription factor, the oncogene c-myc. It is currently in Phase II trials for restenosis and in Phase I/II trials for cancer and polycystic kidney disease. AVI has recently completed a Phase I NEUGENE antisense study that successfully down-regulated the liver enzyme Cytochrome P450 and modified drug metabolism. More information about AVI is available on the Company's Web site at http://www.avibio.com/.

"Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: The statements that are not historical facts contained in this release are forward-looking statements that involve risks and uncertainties, including, but not limited to, the results of research and development efforts, the results of preclinical and clinical testing, the effect of regulation by the FDA and other agencies, the impact of competitive products, product development, commercialization and technological difficulties, and other risks detailed in the Companies' Securities and Exchange Commission filings.